# Copyright (c) 2025 Bytedance Ltd. and/or its affiliates
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import re


def auto_eval(expression, local_vars, default=None):
    if not isinstance(expression, str):
        return expression
    pattern = r"\$(.+)\$"
    matches = re.findall(pattern, expression)
    if len(matches) == 0:
        return expression
    var_name = matches[0]
    try:
        var_value = eval(var_name, {}, local_vars)
        if var_value is None:
            var_value = default
    except:
        var_value = default
    return var_value
